Control apparatus for a gas turbine with a plurality of intermittent type combustion chambers



Apnl 8, 1958 w. HOBSON 2,829,493

CONTROL APPARATUS FOR A GAS TURBINE WITH A PLURALITY OF INTERMITTENT TYPE COMBUSTION CHAMBERS Filed Sept. 24, 1953 3 Sheets-Sheet 1 INVENTOR. WALTER H Bs N,

BY 6 L fih 'es Aprll 8, 1958 w. HOBSON 2,829,493

CONTROL; APPARATUS FOR A GAS TURBINE WITH A PLURALITY OF INTERMITTENT TYPE COMBUSTION CHAMBERS Filed Sept. 24, 1955 a Sheets-Sheet 2 IN VEN TOR. Wnurae H Apnl 8, 1958 w. HOBSON 2,829,493

CONTROL APPARATUS FOR A GAS TURBINE WITH A PLURALITY OF INTERMITTENT TYPE COMBUSTION CHAMBERS Filed Sept. 24, 1955 3 Sheets-Sheet I5 I N V EN TOR. WALJBQ Ho eso 41 United States Patent CONTROL APPARATUS FOR A GAS TURBINE WITH A PLURALITY F INTERMITIENT TYPE COMBUSTION CHAMBERS Thisinvention relates to combustion turbines.

It is the principal object of the present invention to provide a combustion turbine of simplified construction and effective performance.

It is a further object of the present invention to provide a combustion turbineof reduced weight yet sturdy construction.

It is a further object of the present invention to provide a combustion turbine having the operation controlled electrically.

It is a further object of the present invention to provide a combustion turbine of reduced noise and vibration characteristics.

It is a further object of the present invention toprovide a combustion turbine that can be assembled and disassembled with relative dispatch.

It is a further object of the present invention to provide a combustion turbine of standardized structure so that relatively easy modification can be made to satisfy the power requirements.

It is a further object of the present invention to provide a combustion turbine having a minimum number of precision-made parts. I

It is a further object of the present invention to provide a combustion turbine having combustion chambers of the intermittently fired type in which the delivery of the fuel and air to the combustion chambers is controlled in an improved manner. I

It is a further object of the present invention to provide a combustion turbine having combustion chambers of the intermittently fired type and in which a plurality of chambers are provided and in which the sequence of the firing of the chambers is controlled.

It is a further object of the present invention to provide a combustion turbine having combustion chambers of the intermittently fired type in which the discharge of the combustion gases under-pressure is controlled in an improved manner.

It is a further object of the present invention to provide a combustion turbine suitable for operation on a gasoline-air mixture but which may also be operated on other fuels.

Other objects and advantageous features of the present invention will be apparent from the specification and claims.

The nature and characteristic features of the invention willbe more readily. understood from the following description taken in connection with the accompanying drawings forming part hereof, in which:

Figure 1 is a front elevational view showing a preferred embodiment of the present invention, parts being shown diagrammatically;

Fig. 2 is a vertical central sectional view taken approximately on the line 2-2 of Fig. 1;

i Fig. 3 is a fragmentary elevational view showing the outer end of one of the combustion chambers and its associated structure; v v

Fig. 4 is a diagrammatic view showing one group of plates 16 and 2,829,493 Patented Apr. 8, 1958 2 circuit connections for the control of the air and fuel valves and the ignition; and I I Fig. is a diagrammatic view of one of the commutator rings with its contacts, the other contacts being shown in broken lines in one relative arrangement. It should, of course, be understood that the description and drawings are illustrative merely, and that various modifications and changes may be made in the structure disclosed without departing from the spirit of the inven tion.

Like numerals refer to like parts throughout the several views. Referring nowmore particularly to the drawings, the combustion turbine of the present invention preferably includes a front hollow cylindrical housing 10 having a front vertical closure plate 11 removably securedthereto, preferably by bolts 12, and a rear vertical closure plate 13, having a centrally disposed horizontal opening therethrough, removably secured to the housing 10, preferably by bolts 14. A rear housing 15 is provided in axial alinement and in spaced relation with the housing 10, and has a front vertical closure plate 16 and a rear vertical closure plate 17 removably secured thereto, preferably by bolts 18 and 19, respectively. Theclosure 17 have axially alined central openings therethrough which are in turn in axial alignment with the opening in the plate 13. Interposed between the housings 10 and 13 cylindrical runner housing sections 27 and 27a are provided to which the housings 10 and 13 are attached, preferably by bolts and 26 extending through flanges 10a and 15a. The housing sections 27 and 27a are held at the peripheral portionthereof by a plurality of bolts 28.

Within the housing 10, a planetary gearing is provided which includes a pinion 36 mounted on the shaft 30, a pluarlity of gears 37 in engagement therewith and sup-' ported by a plate 37a, the gears being in engagement with an internal ring gear 38 carried on a gear mounting plate 39. The end of the shaft and the interior of the plate 39 have a ball bearing 30a interposed therebetween The planetary as to provide a three to one speed reduction.

A frontstub shaft 40 is provided secured to the gear mounting plate 39. The end of the shaft 40 ispositioned within a bearing 41 carried by the front closure plate 11.

Within the runner housing sections 27 and 27a hubs 44 are provided, secured to the shaft 30 and movable therewith which carry discs 45 to the outer or peripheral portions thereof' blades 46 are secured for driving contac t'of the combustion gases.

An axially extending annular member 47 is provided integral with and disposed on the interior of the radialwall of the housing section 27 and has a passageway 48, in communication with a plurality of delivery passage ways 49 for delivery of the gases of combustion to the blades 46.

An axially extending annular member 50 is provided and disposed onthe interior of the radial wall of the'housing section 27a and has a plurality of dis- 51 in communication with a dis-. charge chamber 52 beyond the annular members 47 and.

integral with charge passageways 50. The housing section 27a is provided with one or more discharge passageways 53 in communication with a discharge pipe 5 A plurality of combustion chambers preferably of a number divisible by three, is provided,

outer end closure wall 61, a cylindrical side wall portion 62 having exterior cooling fins or ribs 63 thereon and, a mounting portion 64 which is adapted to seaton a hollow valve bracket 65, secured to thehousing section 27. p The "bracket 65 has a central valve chamber 66 with a side gearing is preferably of such characteristics V radially disposed. Each of the combustion chambers 60 has an 3 port 67 communicating with the interior of the combustion chamber and an axial passageway 68 connected to one of the pasageways 48.

Within the valve chamber 66 a valve 69 is provided having a plug portion 70 for closing the passageway 68 and a piston portion 71 of larger area than the plug portion 70. A compression spring 72 in engagement with an abutment 73 normally holds the plug portion 70 inlclosedposition and is adjustable by a screw 74 in threaded engagement in a bonnet 75. The bonnet 75 is held on the valve bracket 65 by screws 76. A lock nut 77 may be provided on the screw 74 for holding the spring 72 in the desired adjusted position.

The end closure wall 61 has a port 78 therein with a valve plug 79' for'normally closing the port 78. A sleeve 80 is provided, alined with the port 78 within which a compression spring 81 is mounted. The spring 81 is in engagement at one end with an externally threaded abutment 83 mounted in the sleeve 80 and at the other end with an abutment washer 84 held on a valve stem 85 by a nut 86. The valve stem 85 is con nected to the plug 81. By adjustment of the locations of the abutment 83 or of the washer 84 the spring force of the spring 81 maybe varied as desired.

Oppositely disposed valve housings 87 and 88 are provided having ports 89 in communication with the port 78. The ports 89 are normally closed by valve plugs 90, and held in closed position by springs 91. Solenoids 92 and 93 are provided, in housings 94 for impelling the valve plugs to open position, as hereinafter explained. The solenoids 92 and 93 each have one terminal connectedto ground. The ports 89 have side ports in communication therewith, the ports being in turn in communication with supply pipes 95 and 96, toroidal in shape, to which air and an air-fuel or fuel mixture are supplied under pressure through pipes 97 and 98.

A spark plug 99 is provided in the side wall portion 62 of each chamber 60 for ignition, the plugs 99 being grounded to the chamber 60.

An elongated horizontal drive shaft 30 is provided centrally positioned within the openings inhousings 10 and 13 and the housing 27. The fore part of the shaft 30 has a hub 31 thereon, the outer surface of which has the inner race of a ball bearing 32 mounted thereon. The outer race of the ball bearing 32 ismounted in the interior wall of the housing 10. Similarly, within the housing 15,, the shaft 30 is provided with a hub 33, the outer surface of which has the inner race of a ball bearing 34 secured thereto. The outer race of the ball bearing 34 is mounted in the interior wall of the housing 15. Suitable packings 35 are provided Within the closure plates 13, 16 and 17 and in engagement with the shaft 30 to prevent leakage of gases or lubricants at these locations.

A commutator cylinder 100 is mounted on the shaft tacts 103a connected to the sleeve 102, three being em- The ring 104' ployed for theplanetary gearing shown. is preferably employed for the control of the fuel supply valve solenoids 93.and has circumferentially'spaced contacts 104a in predetermined angular relation to thecontacts 103a. The ring 105 isypreferably employed for the control of the spark plugs 99 and has circumferentially spaced contacts 105a in predetermined angular relation to the contacts 103a and 104a.

An insulated contact member 106 is mounted inthe housing 10 and is connected by a conductor 107 to a suitable source of electrical energy and preferably to the positive terminal of a battery 108 for electrical energy input. The negative terminal of the battery 108 is preferably connected to ground.

A plurality of spaced insulated contact members 109 are provided in the housing 10, for engagement with the ring 103 and the contacts 103a thereon. One of the contact members 109 is preferably connected to the air valve solenoids 92 for the first of each group of three combustion chambers 60, circumferentially considered, the next contact member 109 to the solenoids 92 for the second of each group of three combustion chambers 60, and the last contact member 109 to the third of each group of three combustion chambers 60.

The conductors for connecting the contact members 109 to the solenoids 92 are shown at 110 and may be provided with cut-out switches 111.

A plurality of spaced insulated contact members 112 are provided in the housing 10 for engagement with the ring 104 and the contacts 104a thereon. The contact members 112 are connected to the fuel valve solenoids 92 of the combustion chambers 60 in groups of three, by conductors 113, having cut-out switches 114, in a manner similar to the conductors 110.

A plurality of spaced insulated contact members 115' are provided in the housing 10 for engagement with the ring 105 and the contacts 105a thereon.

The contact members 115 are preferably connected by conductors 116, having cut-out switches 117 therein, through ignition coils 118, to the spark plugs 99, in groups of three in a manner similar to the conductors 110. The coils 118 each have a connection to ground.

The relative angular arrangement of the contact rings 103, 104 and 105 and of the contact members 109, 1.12 and 115, as indicated in Fig. 5, permits of timed introduction in sequence of air for initial scavenging and to support combustion, and offuel for combustion, and the timed firing of the air-fuel mixture in the combustion chambers 60, and carrying out of this sequence of operations in the first, then in the second, and finally in the third combustion chamber 60 of each group of three chambers.

The timing is preferably such thatwhen one combustion chamber 60 is having air supplied thereto, the next contiguous chamber 60 is having fuel supplied thereto and the next chamber 60 has the spark plug 99 thereof firing- If desired, of-course, in place of the charging and firing in groups, the respective combustion chambers could, by rearrangement of the connectors and the provision of additional contacts be charged and fired in circumferential sequence.

The mode of operation will now be pointed out.

The rotation of the shaft 30 drives, thecommutator cylinder 100. The commutator cylinder100 controls the sequence of airand fuel, delivery from the supply pipes 95 and 96-respectively into the chambers 60. The delivery of air and: fuel under pressure is effected through the operation of the valve plugs 90 upon energization of the solenoids 92 and, 93, respectively. Normally, the valve plugs 90 are urged by the springs 9 1jto closed position. Under the control of the commutator cylinder 100 these valves are opened succesively, so that the air supplied precedes the fuel supplied by a predetermined. timeinterval to providea scavenging action. Sufficient pressure is maintained in the supply reservoirs for the air and fuel so that upon the introduction of each the pressure is such that it Will open the valve plug 79 to permit delivery into the chambers 60 butv will prevent passage'of the, ignitedair-fuel mixture from t-hechambers 60.

The valves 69, at. the exhaust ends of the chamber 60 are normally closed to maintain the developed pressure til a-predetermined pressureis built upby the explosion- By adjusting the tension.

of the combustible mixture. of the spring 72 this, action canbe-closely controlled.

. -Uponthe opening of the valve plug 6 by the pressure efiectiveon thegreater area of the piston 71, the explosion gases pass through the pasag-eways 68, 48 and 49 and against the rotor blades 46, and then pass through the passageways 51 to the chamber 52 and then through the passageways 53 to the discharge pipe 54 to exhaust.

The timing of the operating procedure is so regulated that a properly proportioned combustion mixture is supplied to the chambers 60 at the proper instant. Such timing eliminates any tendencies toward flooding with either rich or lean mixtures so that back firing is eliminated and power losses minimized.

During the operation of the turbine a predetermined sequenceof events is occuring in the chambers 60. Assuming any chamber 60 as a first chamber 60, the first chamber 60 receives a charge of air with suflicient pres sure to open the valve 79 to permit this delivery. A portion of this charge of air also serves to clear the first chamber 60 of residual explosion gases of the previous explosion. Proceeding in a clockwise direction, facing the turbine, the second chamber 60 receives a charge of air in rapid successive relation to the first chamber 60, while at the same time the first chamber is receiving a charge of fuel. Finally, the third chamber 60, in rapid successive relation to the second chamber 60, receives a charge of air while at the same time the second chamber 60 receives a charge of fuel and the first chamber 60 is fired. Chambers 60 of other groups are simultaneously following the same cycle so that for every three chambers 60, at any one time, one is receiving air, one is receiving fuel and one is firing. For only three chambers 60, and with three sets of contacts on each commutator ring one explosion occurs for every revolution of the shaft 30; for six chambers 60, two explosions occur for every revolution of the shaft 30; and fornine chambers 60, three explosions occur for every revolution of the shaft 30.

From the description given above it can be seen that the functioning of the turbine can be regulated to satisfy the power demands.

If it is desired to take a combustion chamber 60 or group of such chambers out of action this can be readily accomplished by actuation of the appropriate switches 117 and 114 which control the firing and fuel supply, and also the appropriate switches 111. In this manner explosion hazards due to the discharge of unburned fuel being discharged to the blades 46 may be eliminated. No such isolation of combustion chambers or groups of combustion chambers has heretofore been available.

I claim:

1. A combustion turbine comprising a housing, a drive shaft in said housing, a rotor mounted on said drive shaft,

a plurality of circumferentially arranged combustion chambers mounted on said housing, passageways for connecting said chambers to said rotor for the delivery of gases of combustion to said rotor, pressure actuated valves for controlling said passageways, a combustion air supply valve for each of said combustion chambers, a fuel supply valve for each of said combustion chambers, solenoids for actuating each ofsaid supply valves, ignition plugs in each of said chambers, and means for controlling said solenoids and said plugs in timed sequence, said last means including separate cut-off members for each of said solenoids and said plugs.

2. A combustion turbine comprising a housing, a drive shaft in said housing, a rotor mounted on said drive shaft, a plurality of circumferentially arranged combustion chambers mounted on said housing, passageways for connecting said chambers to said rotor for the delivery of gases of combustion to said rotor, pressure actuated valves respectively movable to open positions by pressure attendant upon combustion in said chambers for controlling said passageways, a connection to a source of air under pressure for each of said combustion chambers, a com bustion air supply control valve in each of said connections, a 'connecticn'to asou'rce of fuel "under pressure.

for each ofsaid combustion chambers, a fuel supply ccmtrol valve in each of said second mentioned connections, a normally closed pressure operatedvalve interposed between said control valves and each of said combustion chambers, solenoids for actuating each of said supply valves, ignition plugs in each of said chambers, and means for controlling said solenoids and said plugs in timed sequence. i a 1 a 3. A combustion turbine comprising a housing, a drive shaft in said housing, a rotor mounted on said drive shaft, a plurality of circumferentially arranged combustion chambers mounted on said housing, said -combustion chambers being in groups ofat least'three, passageways for connecting said chambers to said rotor for the delivery of gases of combustion to said rotor, pressure actuated valves respectively movable to open positions by pressure attendant upon combustion in said chambers for controlling said passageways, a connection to a source of air under pressure for each of said combustion chambers, a combustion air supply control valve in each of said connections, a connection to a source of fuel under pressure for each of said combustion chambers, a fuel supply control valve in each of said second mentioned connections, solenoids for actuating each of said supply valves, ignition plugs in each of said chambers, and means: for controlling said solenoids and said plugs in timed sequence, said last means being connected. to said solenoids and said plugs to sequentially supply air and fuel charges and ignition impluses to the first, second and third chambers of each group.

4. A combustion turbine comprising a housing, drive shaft in said housing, a rotor mounted on said drive shaft, a plurality of circumferentially arranged combustion chambers mounted on said housing, passageways for connecting said chambers to said rotor for the delivery of gases of combustion to said rotor, pressure actuated valves respectively movable to open positions by pressure attendant upon combustion in said chambers for controlling said passageways, a connection to a source of air under pressure for each of said combustion chambers, a combustion air supply control valve in each of said connections, a connection to a source of fuel under pressure for each of said combustion chambers, a fuel supply control valve in each of said second mentioned connections, solenoids for actuating each of said supply valves, ignition plugs in each of said chambers, and means for controlling said solenoids and said plugs in timed sequence, said last means including moving contacts in spaced relation driven by said shaft and connections from said contacts to said solenoids and said plugs for sequentially supplying air, fuel and ignition impulses to each chamber, said last means also including separate cut-off members for each of said solenoids and said plugs.

5. A combustion turbine comprising a housing, a drive shaft in said housing, a rotor mounted on said drive shaft, a plurality of circumferentially arranged combustion chambers, mounting members on said housing for said combustion chambers, passageways in said mounting members for connecting said chambers to said rotor for delivery of gases of combustion to said rotor, a pressure actuated valve in each of said mounting members for controlling said passageways, a connection to a source of air under pressure for each of said combustion chambers, an air supply control valve in each of said connections, a connection to a source of fuel under pressure for each of said combustion chambers, a fuel supply control valve in each of said second mentioned connections, operating members for actuating each of said supply valves, ignition plugs in each of said chambers, and means for controlling said operating members and said plugs in timed sequence.

6. A combustion turbine as defined in claim 5 in which the combustion chambers are in a plurality of groups of three, and the control means is connected to sequentially supply an air charge, a fuel charge and an ignition imgroup.- i

7. A combustion turbine as defined in claim 5 in which the control means includes moving contacts in spaced relation and connections from said contacts to said operating. members and. said plugs for sequentially supplying air, fuelcand iguitionimpulses toveach chamber in spaced timed relation to the supplying to contiguous chambers.

8. A combustion turbine as defined in claim 5 in which the combustionchambers are ina plurality of groups of three, and the control means includes moving contacts in spaced relation andconnectionstrom said contacts to said operatingnmem'bers andsaid plugs for sequentially supplying air, fuel and ignition impulses to the first, second and third chamber of each group in spacedtinied relation to the supplying to contiguous chambers References Cited in the file of this patent UNITED STATES PATENTS 

